Most commonly recommended herbicide Command 480 EC applied preemergence causes permanent damage deteriorating quality of the yield in susceptible cultivars. In this situation, it is necessary to search for some effective herbicides that do not show phytotoxic effects on cultivars of different genetic traits. Field experiments conducted in the years 2009-2013 were set up on two different soils. The experiments studied response of four cultivars of winter oilseed rape: population Monolith, improved population ES Bourbon and Canti, and hybrid Nelson on herbicides Nimbus 283 SE and Butisan Star 416 SC applied pre-emergence. Impact of herbicides in the form of a mixture of metazachlor with clomazone, and metazachlor with chinomerac, on morphology and quality of the yield of winter oilseed rape cultivars was compared to clomazone used in the form of Command 480 EC. Symptoms of phytotoxic effects of these mixtures in each case were milder than of clomazone. Mixture of metazachlor with chinomerac proved to be the safest in relation to all cultivars, and showed no phytotoxic effect in the growing season. The studies of residues of active substances showed an increased occurrence of clomazone after using herbicide Command 480 EC, and of metazachlor when using Nimbus 283 SE in the seed cultivars ES Bourbon and Monolith, especially when cultivated in luvisols. In any case, the level of these residues did not exceed acceptable standards. The studies of quality traits of the cultivars showed no significant effects of the herbicides on the protein and fat content in seeds. Cv. Monolith showed the highest variability in the yield in years and locations, regardless of the used herbicide.

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